Because “Appropriate Behavior” is set in Brooklyn and focuses on the romantic confusion and misadventures of Shirin, a headstrong young Iranian-American woman adrift in hipsterland, this lively romantic comedy starring Desiree Akhavan, who wrote and directed, has inevitably been compared to “Girls.” Shirin’s brash, off-kilter attitude is not unlike that of Lena Dunham’s Hannah Horvath. Both are self-centered, impulsive and brusque. But there are few signs that Shirin possesses Hannah’s driving career ambition. When Shirin takes a job teaching filmmaking to kindergartners, the little tykes run her ragged.

Ms. Akhavan, who from certain angles resembles Hilary Swank, has a face so expressive that you can hardly avert your eyes once she appears; every few seconds, a little storm passes across her features. Shirin, who calls herself bisexual, is smarting from her breakup with her first girlfriend, Maxine (Rebecca Henderson), whose apartment she exits toting her luggage and a conspicuous strap-on dildo.

The movie jumps around in time so abruptly that you can easily lose your bearings. Shirin’s relationship with Maxine begins almost as a whim on the steps of a Park Slope brownstone on New Year’s Eve and breaks off just as suddenly, with an eruption that leads to the throwing of bottles. There are no discussions about their relationship or attempts at reconciliation. Boom. It’s over.

Shirin is much more immature than Hannah. Her default expression is the glowering, willful pout of a child on the verge of a tantrum. She leaps headlong into sexual adventures, including a threesome. What drives her isn’t desire so much as a bored curiosity. I have no idea if “Appropriate Behavior” presents an accurate picture of the hookup rites of Brooklyn’s hipoisie. But these blasé couplings suggest a climate in which the instinct for emotional self-protection dampens erotic passion.

Ms. Akhavan’s performance makes it clear that Shirin’s attraction to men, though genuine, is less intense than her feelings for women, especially for the casually butch Maxine. A major reason for their discord is Maxine’s impatience with Shirin’s reluctance to come out to her supportive but strait-laced parents, who dote on their soon-to-be married son (Arian Moayed), a doctor. When she finally musters the nerve to tell her mother that she is bisexual, her mother haughtily retorts, “No you’re not.”

For all its disorganization and lack of an ending or even a sense of direction, “Appropriate Behavior” is alive. The screenplay is packed with smart remarks, clever and unpredictable turns of phrase that knock you off balance. Little set pieces in which Shirin goes shopping for sexy lingerie and takes part in a gay-rights discussion group give you the flavor of a neighborhood in which everyone has an edge. A stoned, laid-back attitude is not the same thing as relaxation.